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DeviceNet
DeviceNet Termination Resistor
At the extremes of the network a termination resistor must be installed, which has the objective of reducing possible signal
reflections on the network. These can cause disturbances in communication, with constant and random stops and eventually total
interruption of operation.
The terminating resistor must be 121 Ω, but it is assumed to have the commercial value of 120 Ω with a required minimum power
dissipation of ¼ W.
Terminating Resistor Connection
The 120 Ω resistor should be connected between the communication wires (CAN_H and CAN_L) at the two distribution boxes at
the ends of the network, at the points that have the largest distance from each other.
A practical way to verify if a network has been terminated correctly is measure
the resistance between the communication wires blue and white, if the result is
approximately 60 Ω this indicates that the resistors are present on the network.
DeviceNet Communication
Setting the Address
The address can be set in 3 ways - by the software configuration, via handheld or by the menu on the M-VUE unit.
M-VUE can be addressed from 00 to 63.
To set the address at the M-VUE unit, please see “Setting the Address” section.
Note: M-VUE cannot have the same address as other network equipment, if this occurs the equipment with the same address will
not work.
After setting the address, the user must set the rate at which the M-VUE will communicate in the network.
Baud Rate
The Baud Rate can be set to 125, 250 or 500 Kbit/s.
To set the baud rate at the M-VUE unit, please see setting “Setting the Speed/Baud Rate” section.
The communication rate must be set to be the same as that used by other equipment in the network.
